Mechanical movement for seam cap riveting and the like



June 12, 1956 a. T. HARCOURT MECHANICAL MOVEMENT FOR SEAM CAP RIVETINGAND THE LIKE z sneets-sheet 1 Original Filed May 11, 1948 l1|||I/CHPIIII INVENTOR. GEORGE T A R/PC0057 June 12, 1956 G. T. HARCOURT2,749,760

MECHANICAL MOVEMENT FOR SEAM CAP RIVETING AND THE LIKE Original FiledMay 11, 1948 2 Sheets-Sheet 2 INVENTOR. v 650E615 7. HflRCOURTHTY'OR/YEY MECCAL MOVEMENT FOR SEAM CAP RIVETING AND THE LIKE George T.Harcourt, Detroit, Mich, assignor to Chicago Pneumatic Tool Company, NewYork, N. Y., a corporation of New Jersey Original application May 111948 Serial No. 26,296 Divided and this application November 2, 1950,Serial No. 193,591

4 Claims. (Cl. 74---110) This invention relates to mechanical movementsand more particularly to a drive mechanism for portable riveting tools.Such riveting tools are useful in effecting seam cap rivetingoperations. This application is a division of my original application,Serial No. 26,296, filed May 11, 1948, now Patent 2,539,419, datedJanuary 30, 1951, relating to a hydraulic tool for riveting seam caps onrailroad car roofs.

Seam cap riveting is illustrated in United States Patent 2,085,540,issued June 29, 1937, to Walter P. Murphy and which concerns a roofconstruction for metal freight cars. In effecting such operations, it isessential that the folds of metal which comprise the seam cap assembly,must be securely held and clamped prior to and during the rivetingoperation if a good rivet setting is to be effected. The seam capassembly may also include brackets for the car running board which aresometimes riveted with the seam cap and which complicates the rivetingoperation.

It is an object of the present invention to provide a portable hydraulicriveter which can be conveniently used by an operator to eflicientlyrivet a seam cap assembly for car roofs of the type shown in the abovementioned patent.

It is another object of the present invention to provide a drivemechanism for a portable hydraulic riveter which includes a rockermember pivoted within the riveter housing which has dependableconnections with the respective actuating and actuated members andwherein control of the rocker through its respective connections withthe members during the power stroke are independent of the pivot pinswhich are connected between the rocker and the members.

Other objects of the invention are to provide a mechanical drivemechanism for portable riveters which is of simple, sturdy and ruggedconstruction, compact, inexpensive to manufacture, reliable inoperation, extremely serviceable, has low maintenance costs, has aminimum number of parts and efiicient in operation.

For other objects and for a better understanding of the invention,reference may be had to the following detailed description taken inconnection with the accompanying drawing, in which Fig. 1 is a sideelevational view of the portable car roof seam cap riveter embodying thedrive mechanism of the present invention, with portions broken away toshow the drive mechanism and the interior construction of the riveter.

Fig. 2 is a fragmentary longitudinal sectional view of the slotted rearend of the actuated member which in this case is a ram or rivet setholder and showing in broken lines a part of the rocker arm whichactuates the actuated member or holder, the view being taken generallyon line 22 of Fig. 5.

Fig. 3 is a transverse sectional view of the riveter taken on line 33 ofFig. 1 and looking in the direction of the arrows thereof.

States Patent Fig. 4 is a fragmentary side elevational view of theriveter showing the pivotal connection of the rocker with the riveterhousing, the view being taken looking along line 44 of Fig. 3.

Fig. 5 is a fragmentary longitudinal sectional view of a portion of theriveter and taken through the connection of the rocker with the actuatedmember of rivet set holder and generally on line 5-5 of Fig. 1.

Referring now particularly to Fig. l, the seam cap assembly upon whichthis riveter is used comprises a rivet 14 extending horizontally throughflanged ends of two adjacent roof sheets 15 and through a seam cap 16 ofinverted U-shape which snugly embraces the flanged ends of the roofsheets. The seam cap 16 extends transverse- 1y across the roof of thecar at a slight inclination from a horizontal plane and near the centerof the roof serves as a support for running board brackets 17. Thepresent riveter is designed to press the sides of the seam cap intotight contact with the roof sheet flanges and then to head the rivet 15with a squeezing action. The head of the rivet 14 may engage the seamcap directly or may be separated therefrom by a flange of the bracket17, as shown, depending upon the location of the riveting operationalong the seam cap assembly. The present riveter is designed to permitvariations in the length of the rivet and in the total thickness of theassembled Work pieces.

A yoke 18 is formed to house and support the various elements of theriveter. The yoke 18 is preferably a steel castingwhich is generallyhollow and wherein the walls of the yoke are thin to provide minimumweight and maximum strength in accordance with well known principles ofdesign. The yoke 18 has a bay 19 adapted to provide sufficient clearancefor the work assembly and to permit the riveter to be moved bothangularly and longitudinally of the running board brackets 17.

In the upper portion of the yoke or housing 18 is an open ended cylinder21 which is maintained in place by virtue of its press fit with annularprojections 22 and 23 extending inwardly from the walls of the yoke 18.A shoulder 24 on the cylinder 21 at its open end abuts the projection 23to hold the same against forward movement within the yoke or housing 18.Threadedly secured to the open end of the cylinder 21 is a cylinder head25 in which there is a passageway 26, one end of which opens into thecylinder 21 and the other end of which is threaded for the reception ofa hose fitting 27 that projects into an opening 28 in the top wall ofthe yoke or housing 18. The cylinder head is locked in place by means oftwo set screws 29, 29, Fig. 3. These set screws pass through theopposite walls of the yoke 18 and engage the cylinder head 25, as shown.The closed end of the cylinder 21 has a threaded opening 31 whichreceives an elbow fitting 32 to which is secured a hose connection 33,that passes outwardly through an opening 34- in the top wall of the yokeand being generally aligned with the hose fitting 27. Within thecylinder 21 is a slidably operated piston 35 to which is connected apiston rod or actuating member. 37 that passes through a smooth bore 38in the cylinder head 25.

The end of the piston rod 37 which projects from the cylinder 21 beyondthe cylinder head 25 has an enlargement 40 that is bifurcated therebyproviding a vertically extending slot 39 which receives the upper end ofa rocker 41 enclosed within the yoke 18 and pivotally connected thereto.The enlarged end of the piston rod 37 is indicated generally at 40. Onthe opposite walls of the slot 39 are respectively vertically extendinggrooves 42 opposing each other which are adapted to receive the ends ofa guide pin 43, Fig. 3, that is retained in the upper end of the rocker41. It will be noted, as viewed tue of the upper end of the rocker 41having a curved or I rounded projection 44 that abuts the bottom 39 ofslot 39 in the enlargement 40 of the piston rod 37 during the powerstroke movement of the piston and of the rocker The rocker 41 has a hubenlargement 41 with a central opening 41" therein. The rocker 41 isfixed to a pivot pin 45, each end of which is maintained in nestedneedle bearings 46, Figs. 3 and 4, which are surrounded by a bushing 47that is press fitted in a bore 48 formed in the wall of the yoke 18. Ateach end of the pin 45 is a closure plate 49 that fits the bore 48 andwhich is secured by a screw 51 to the end of the pin 45 and whichprevents the outward displacement of the several nested needle bearings46. There is a needle bearing assembly at each end of the pin 45.

The lower end of the rocker 41 has a curved or rounded projection 52which abuts a rivet set holder or actuated member 53 slidably supportedin bushing 54, Fig. 5, which is press fitted in a bore in the rear jawof the yoke 18. The end of the rivet set holder 53 which engages therocker 41 is bifurcated to provide slot 55' and has two verticallyextending grooves 55 arranged respectively in the opposite walls of theslot 55' to receive the respec tive ends of a pin 56 retained in thelower end of the rocker 41. The pin 56, in acting on the sides of thegrooves, serves to transmit return stroke movement from the rocker 41 tothe rivet set holder 53 in a manner similar to the action of pin 43 inthe grooves 42 of the piston rod enlargement 40. During the power strokemovement of the rocker 41, the rounded projection 52 of the rockerengages the bottom of the slot 55 of the rivet set holder 53, so thatthere is no strain upon the pin 56. The axis of the pivot pin 45 iscloser to the axis of the rivet set holder 53 than to the axis of thepower piston 35 whereby the force of the piston is multiplied in thewell known manner. A rivet set 57 is tightly fitted in a bore 53 in therivet set holder, Fig. 5, and may be easily removed when worn or when adifferent size or style of rivet is to be set by means of shoulder 58,Fig. 1. This shoulder 58 is formed on the outer periphery of the rivetset and against which can be driven a wedge to force the rivet set 57from the holder 53.

On the forward jaw of the yoke 18 and opposite the rivet set is apressure pad arrangement 59 having a pressure pad 60 adapted to engagethe seam cap assembly and connect it with front toggle links 61, one ofwhich being shown in Fig. 1, that are pivotally connected to rear togglelinks 62. Adjustment screws 64, one shown, control the operation of thelinks. A dolly 69 is tightly fitted within the forward jaw of the yoke18. The pressure pad 60 is thus arranged for reciprocal motion to andfrom the rear yoke jaw in a fixed plane. The dolly 69 receives the rivet14 and the rivet is upset thereby. The pressure pad arrangement is soarranged as to provide maximum clamping pressure of the work prior toand at the commencement of the riveting operations followed by anautomatic decreasing in pressure so that at the time the rivet upsettingbegins, the greater part of the power of the work cylinder, which isapplied to overcome the resistance of the pressure pad, is applied toupsetting the rivet.

At the rear of the yoke 18 is a plate 80 having a hollow handle 81. Atrigger 82 of a switch assembly lying within the handle 81 to whichaccess is had by removal of a closure plate 83. An electric cable 84extends from .4 the handle and may extend to a valve or the like whichcontrols the supply of fluid to the cylinder 21.

The riveter is suspended from a bail 93 that is connected to the frontend of the yoke 18 by a trunnion arrangement 94. This arrangement has anarm 101 that may engage a stop 102 to limit the rotation of the trunnionarrangement 94.

In operation, the riveter is positioned so that the rivet set 57contacts the head of the rivet 14 which is located in a hole in the workpieces, the other end of the rivet extending through the work piece inthe direction of the pressure pad 59 or dolly 69. The trigger 82 ispressed initiating operation of the power plant, not shown, andresulting in the pressurized oil being delivered to the cylinder throughthe hose connection 33. The piston 35 is forced rearwardly in thecylinder 21 causing the rocker 41 to be rotated in a clockwise directionabout the pivot pin 45 thereby tending to drive the rivet set holder 53forward and in the direction of the forward jaw of the yoke 18. However,since the holder 53 abuts the work piece by way of rivet set 57, thework piece being stationary, prevents forward movement of the rivet setholder 53, with the result that the motion is transferred to the yoke18, which thereupon moves in a rearward direction in unison with thepressure pad 60 causing the pad to engage the work piece or the seam capassembly in the manner as illustrated. Continued movement of the yoke 18causes the pressure pad 60 to tightly squeeze the work piece until thedolly 69 moves rearward relative to the pressure pad and contacts therivet. The operator then observes through transverse slot 104 in thepressure pad 60 Whether or not the dolly 69 and the rivet 14 areproperly aligned, releasing the trigger if necessary to prevent thisoperation. If the trigger is kept pressed, the oil pressure andmechanical pressure is built up rapidly and the rivet heading operationbegins, but the effect of the pressure pad 60 is gradually diminished asthe mechanical advantage of the toggle links 61 and 62 increases.

When the rivet heading is completed in the dolly and the piston 35 hastravelled its maximum distance, the pressure in the high pressuredelivery hose builds up to such a value as to automatically reverse theoperating cycle of the power plant, whereupon the oil in the highpressure hose is released and low pressure oil is delivered to thecylinder 21 by way of the hose connected to the fitting 27, therebyforcing the piston 35 to return to its first position in the cylinder.In so doing, the rocker 41 is moved in a counterclockwise direction thuscausing the return of the rivet set holder 53 and the pressure padarrangement 59 to their initial position so that the riveter can beremoved for positioning for subsequent riveting operations.

During both the power and return strokes, the movement of the rocker iseffected. With the curved or rounded projections 44 and 52 on the armsof the rocker which engage with the bottoms of the slots in which theyextend, the use of the pins 43 and 56 is eliminated during the powerstroke. The pins 43 and 56 are used only upon the return stroke of thepiston and the rocker is rotated in a counterclockwise direction. Themovement of the rocker at this time is when there is no strain upon themembers. The pins 43 and 56 being of less diametrical width than thewidth of the slots to permit the easy engagement of the roundedprojections 44 and 52 with the bottom of the slots.

It should now be apparent that there has been provided a mechanicalmovement and drive mechanism for riveters wherein there is littleopportunity for breakage of parts and that the life of the connectingpin between the ends of the rocker is increased inasmuch as the powerstroke pressure is not placed upon the pins and wherein adequatevertical displacement of the pins and the slots or grooves is permittedto prevent binding of any of the parts.

While various changes may be made in the detail construction, it shallbe understood that such changes shall be within the spirit and scope ofthe invention as defined by the appended claims.

I claim:

1. In a mechanical movement, an actuating member having a bifurcatedportion thereby forming a slot, a supporting member, a rocker pivotedupon the supporting member, said rocker having an arm with a curvedprojection adapted to cooperate with the bottom of the slot of theactuating member, said rocker having a second arm with a curvedprojection, an actuated member having a bifurcated portion with a slottherein, said curved projection of the rocker second arm beingengageable with the bottom of the slot of the actuated member, wherebythe pressure being applied by the actuating member and to the actuatedmember is applied through the curved projections, and the bifurcatedportions of the actuating and actuated members having respectivelyopposing vertically extending grooves, a pin in each arm of the rockerand extending into the grooves of the bifurcated portion of theassociated member, said pins being of less diameter than the width ofthe vertically extending grooves.

2. In combination, a supporting member, slidable actuating and actuatedmembers mounted in the supporting member for adjustment, each of saidslidable members having an end slot providing bifurcated portions, arocker member pivoted upon the supporting member and having its oppositeends lying respectively in the respective slots of said members andengaging respectively with the bottoms thereupon whereby upon theactuating member being operated power is transmitted to and from therocker member through the edge thereof, and the bifurcated portions ofat least one of said slidable members having vertically extendinggrooves on their inner faces thereof and opposing one another, a pinlying in said grooves and extending through the rocker whereby to eflectthe return movement of the rocker.

3. In combination, a supporting member, slidable actuating and actuatedmembers mounted in the supporting member for adjustment, each of saidslidable members having an end slot providing bifurcated portions, arocker member pivoted upon the supporting member and having its oppositeends lying respectively in the respective slots of said members andengaging respectively with the bottoms thereupon whereby upon theactuating member being operated power is transmitted to and from therocker member through the edge thereof, and the edge of said rockermember having rounded portions for engagement with the respectivebottoms of the slots of the slidable members, and the sides of thebifurcated portions of each of the members having respectivelyvertically extending grooves opposing one another, a pin connected toeach end of the rocker and extended through the rocker end and into thegrooves of the member.

4. In a mechanical movement, a supporting means, an actuating memberarranged for reciprocable movement Within the supporting means andhaving an end portion with an open ended slot, a rocker arranged forpivotal movement Within the supporting means, said rocker having a firstarm with a curved projection adapted to engage the bottom of the slot ofthe actuating member, an actuated member arranged for reciprocablemovement within the supporting means and having an end portion with anopen ended slot, said rocker having a second arm with a curvedprojection adapted to engage the bottom of the slot of the actuatedmember, and means connecting the actuating and actuated members with therespective arms of the rocker so that said curved projections aremaintained in close proximity to the bottom of the respective slots.

References (Zited in the file of this patent UNITED STATES PATENTS1,605,402 Hay Nov. 2, 1926 1,886,241 Chapman Nov. 1, 1932 2,053,720 HuckSept. 8, 1936 2,083,334 Harcourt June 1, 1937 2,276,301 Gregory Mar. 17,1942 2,365,154 Storz Dec. 19, 1944 2,387,449 Kaman Oct. 23, 19452,399,907 Blair May 7, 1946 2,439,284 Buckwalter Apr. 6, 1948 FOREIGNPATENTS 829,888 France Apr. 25, 1938

